Inhaled allergens and irritants are known to elicit recurrent airway obstruction. Human patients suffering from asthma also often experience atopic dermatitis. Cats and dogs demonstrate similar manifestations of atopic dermatitis concurrent with asthma. Recently, horses with RAO and IBH have been diagnosed with recurrent urticaria. The researchers consider that such multiple hypersensitivities suggest a common immunogenetic background.

They noted that a horse with an allergic skin disorder might also experience a hyper-reactive airway (AH). Both RAO and IBH are different in their immunopathology and genetic variations. IBH is considered a Type 1 allergy that includes eosinophilic and mast cell involvement whereas they report that the immunopathology of RAO is still not clear. There is suggestive evidence from clinical human studies that the skin “is an important route of sensitization to asthma-inducing allergens.”

The authors concluded: “Although future studies may identify the immunogenetic basis for this phenomenon, our results already suggest that horses suffering from IBH have a higher risk for AH and therefore might be predisposed to develop equine asthma in the future. These findings should be taken into account when evaluating IBH-horses presented for subtle respiratory signs.”

High enema therapy a plausible method to assist in rehydration of horses in need, especially those not able or willing to voluntarily consume water, or where oral or intravenous replacement therapy is not possible.

It is generally assumed that horses housed in barns with manure collected every day or two from the stalls are not at risk of ingesting infective larvae of internal parasites (cyathostomines) unless they are turned out on pasture. That premise has been modified based on recent research.